I have a robot that looks like the Ubiquity: differential drive, two powered wheels and two casters offeet casters. I like the stability it gives and that it’s more rugged than a ballbearing-wheel.
I works mostly correctly. However not really. If the robot is going straight the casters are aligned and it goes straight. Now if I request a turn, especially a sharp turn (going very slowly) the casters take a moment or three to re-aligh around the turn. Similarly if I stop the robot while it was in a sharp turn and then start again asking for forward, initially the casters make it turn more.
As a result it seems like accurate positioning of the robot is very bad. If it needs to drive forward 10 cmd and it had been turning there’s no way to do it. This makes SLAM navigation really struggle.
Does the Ubiquity have this problem? How does it solve it? Any suggestions? Is it the case that if I want any kind of accurate positioning this configuration just won’t work? What are alternatives? I need this robot to work outdoors so the little ballbearing casters are not really an option.
Thanks for your insights!
Faculty, Computer Science